A multi-year project with tremendous impact

The Oregon State University Dam Impacts Database (OSU DID) is a multi-year effort to create a global database tracking the social and ecological impacts of dam construction projects.

The project is led by Dr. Bryan Tilt, who specializes in cultural and environmental anthropology and international development.


The goal of this project is to provide a macro-level understanding about broad trends related to the impacts of dam construction around the world. 

Although researchers have compiled partial databases of large dams, most of this work has focused on either physical characteristics—such as dam height, location, or catchment size—or on environmental impacts—such as effects on flow regimes and aquatic species.

In comparison, relatively little attention has been paid to social impacts. Thus, the OSU DID was conceived to track the ecological and social impacts of dam construction, such as involuntary population displacement and resettlement, effects on local ecosystems, and effects on fishing and agriculture. 

If government agencies and development organizations properly understand the impacts of dam construction, they can better plan for mitigation and compensation for affected people.

The OSU DID is driven by three central research questions:
  1. What role does geography play in the impacts caused by dam construction? In other words, are resettlement outcomes different across countries or regions?
  2. How have dam impacts changed over time? In other words, are resettlement outcomes getting better or worse?
  3. What is the role of institutions in shaping the impacts of dams? In other words, are resettlement outcomes different under different management authorities, such as international financial institutions, domestic government agencies, or private firms?
Project methods

Our research team started with information provided by the International Commission on Large Dams (ICOLD) and the Global Reservoir and Dam Database (GRanD, McGill University). We narrowed our focus to dams built in developing countries (non-OECD members) between 1960 and 2010, and started with the dams located in the largest river systems.

Our research team then collected information about each dam project from published sources including: peer-reviewed journal articles; international development organization reports; hydropower corporation reports; government documents; non-governmental organization reports; and media reports. Users may download the full bibliography.

Database contents

In addition to a precise geographic location for each dam project, the database includes information on a range of social and ecological variables for each dam, including:

  • The number of displaced people or households
  • Compensation for affected people, both monetary and non-monetary (e.g., land or housing)
  • The financial institutions that funded the project
  • Effects on socially or economically vulnerable populations
  • The benefits and functions of the project
  • Ecological impacts

Users will notice that some dams still have incomplete information at this time. If you have data you’d like to contribute to the project, please refer to our data submission form.